干一干在线中文字幕_最新国内精品自在自线视频_欧美亚洲中文高清_91精品91久久久中77777

Jingning County is located in the east of Gansu Province, located in the hilly and ravines of the Loess Plateau, and the soil is mainly loess, accounting for 91.18% of the county's soil area. THE ORGANIC MATTER CONTENT IN THE SOIL WAS 0.92, THE TOTAL NITROGEN CONTENT WAS 0.072, THE AVAILABLE PHOSPHORUS WAS 8.24PPM, AND THE AVAILABLE POTASSIUM WAS 170.1 PPM.